Light emitting device package and backlight unit having the same

ABSTRACT

Provided are a light emitting device package in which lens tilting is prevented to reduce luminance and color deviations and a backlight unit having the same. The light emitting device package includes an encapsulation material disposed on a substrate to surround a light emitting device and a guide member disposed on the encapsulation material to guide an assembly path of a lens. The guide member includes a first inclined surface having a first inclination to guide a light incident part of the lens and a second inclined surface having a second inclination greater than the first inclination to further guide the light incident part of the lens.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of a U.S. patent application Ser. No.14/468,771, filed on Aug. 26, 2014, which claims priority to KoreanPatent Application Nos. 10-2013-0101485 filed on Aug. 27, 2013,10-2013-0101486 filed on Aug. 27, 2017, and 10-2013-0203477 filed onOct. 10, 2013, and all the contents of which are incorporated herein byreference in their entirety.

BACKGROUND

The present disclosure relates to a light emitting device package and abacklight unit having the same, and more particularly, to a lightemitting device package in which lens tilting is prevented to reduceluminance and color deviations and a backlight unit having the same.

Light emitting diodes (LEDs) represent a kind of semiconductor device inwhich a PN-junction diode using a compound semiconductor is formed toconstitute a light emitting source, thereby realizing light havingvarious colors. Such a light emitting device may have a long life cycle,be miniaturized, and be lightweight. Also, since the light emittingdevice has good light orientation, the light emitting device may operateat a low voltage. Also, such an LED may have superior impact andvibration resistance, and a preheating time and complicated operationmay be unnecessary. In addition, since the LED is packaged in variousshapes, the LED may be modularized for various uses and thus be appliedto lighting devices or display devices.

SUMMARY

In a direct type light emitting device package that is widely used for abacklight unit, light emitted from the light emitting device package maybe primarily widely spared through a secondary lens so that thebacklight unit is reduced in thickness, and also the light is uniformlyemitted onto a light guide plate.

However, in the light emitting device package according to the relatedart, when the secondary lens is assembled, the secondary lens may betilted to cause luminance and color deviations. Thus, lightcharacteristics may be deteriorated due to the luminance and colordeviations to significantly reduce uniformity of light emitted onto alight guide plate or display panel, thereby causing product defects.

To solve the above-described limitations, the present disclosureprovides a light emitting device package in which a lens is easilyaligned by using a guide member, a degree of precision in assembly ofthe lens is improved to prevent luminance and color deviations fromoccurring in a display device, thereby improving light characteristicsand thus producing quality products, the lens is aligned in multi-stagesto prevent the lens from being damaged, thereby easily aligning thelens, and an encapsulation material or substrate is completely insertedinto a light incident part of the lens to realize slimness of theproduct, and a backlight unit having the same. However, this may bemerely illustrative, and thus the present disclosure is not limitedthereto.

In accordance with an embodiment, a light emitting device package mayinclude: a substrate; a light emitting device disposed on the substrate;an encapsulation material disposed on the substrate and configured tosurround the light emitting device; a guide member disposed on theencapsulation material and having at least one inclined surface to guidea light incident part of a lens; and the lens having at least oneengaging surface to contact the guide member.

The guide member may include a top surface, and the at least oneinclined surface includes a first inclined surface inclined to the topsurface, and a second inclined surface inclined to the first inclinedsurface.

The guide member may further include a round edge disposed between thetop surface and the first inclined surface.

The guide member may further include: a flat top surface and a bottomsurface having an area larger than that of the top surface to contactthe encapsulation material.

The guide member may further include: a top surface, a bottom surfaceconfigured to contact the encapsulation material, and a stopperconfigured to contact the at least one engaging surface of the lens.

The at least one engaging surface may include a bottom engaging surfacewhich is supported by the stopper, and the stopper may be disposed to bemore distant from a light axis of the light emitting device than the topsurface.

The at least one engaging surface may include an inner engaging surfaceto contact the guide member, and the inner engaging surface may includean angle of inclination of about 90° with respect to the substrate.

The lens may further comprise a part fixed to the substrate. The lensmay be disposed to be more distant from the light axis of the lightemitting device than the guide member.

In accordance with another embodiment, a backlight unit may include: anencapsulation material disposed on a substrate to surround a lightemitting device; a guide member disposed on the encapsulation materialto guide an assembly path of a lens; and a light guide plate disposed ina path of light emitted from the light emitting device, wherein theguide member includes: a first inclined surface having a firstinclination to guide a light incident part of the lens; and a secondinclined surface having a second inclination greater than the firstinclination to further guide the light incident part of the lens.

In accordance with yet another embodiment, a light emitting devicepackage may include: a substrate, a light emitting device disposed onthe substrate, an encapsulation material disposed on the substrate andconfigured to surround the light emitting device, and at least one guidemember having at least one inclined surface to guide a light incidentpart of a lens. The at least one inclined surface may be formed at aside surface of the encapsulation material, the lens may have a lightincident part which is an inner hollow portion, and the light incidentpart may have an engaging surface to contact the encapsulation materialand the substrate.

The at least one inclined surface may include: a first inclined surfaceinclined to a top surface of the encapsulation material, and a secondinclined surface inclined to the first inclined surface.

The engaging surface may include an inner engaging surface of which anangle of inclination is about 90° with respect to the substrate.

The substrate may further include a side surface engaging with theengaging surface.

The lens may further include a bottom surface disposed at a same levelas a bottom surface of the substrate.

In accordance with still another embodiment, a light emitting devicepackage may include: a substrate, a light emitting device disposed onthe substrate, a lens having a light incident part which is an innerhollow portion, and a guide member having at least one inclined surfaceto guide the light incident part of the lens. The guide member may beconfigured to be snap-fitted into the light incident part.

The at least one inclined surface may include a first inclined surfaceinclined downward toward the substrate, and a second inclined surfaceinclined to the first inclined surface.

The light emitting device package may further include an encapsulationmaterial disposed on the substrate and configured to surround the lightemitting device, and the guide member may be formed on the encapsulationmaterial.

In accordance with still another embodiment, a light emitting devicepackage may include: an encapsulation material disposed on a substrateto surround a light emitting device; and at least one guide memberdisposed on a side surface of the encapsulation material to contact thelens and guide an assembly path of the lens.

The encapsulation material may be a plate having a substantiallycircular shape or a plate having a substantially quadrangular shape withrounded corners, and the guide member may be integrally molded with theencapsulation material and may be a side surface portion of theencapsulation material that is completely inserted into the lightincident part of the lens.

The guide member may include a first inclined surface portion having afirst inclined surface to guide the light incident part of the lens; asecond inclined surface portion having an inclined surface that isrelatively sharply inclined when compared to the first inclined surfaceportion to further guide the light incident part of the lens; and acontact part having a contact surface that the light incident part ofthe lens finally contacts and is fixed thereof.

The first inclined surface portion may have an inclined internal angleof about 100° to about 150° with respect to the top surface portion, andthe second inclined surface portion may have an inclined internal angleof about 150° to about 175° with respect to the first inclined surfaceportion.

The light emitting device package may further include a substrate onwhich the light emitting device is seated, the substrate supporting theencapsulation material; and at least one substrate guide part disposedon a side surface of the substrate to guide to guide an assembly path ofthe lens.

The substrate may be a plate having a substantially circular shape or aplate having a substantially quadrangular shape with rounded corners,and the substrate guide part may be a substrate guide side surfaceportion that is completely inserted into the light incident part of thelens.

A hook surface portion corresponding to the hook part disposed on thelight incident part of the lens may be disposed on the substrate guidepart or the encapsulation guide part.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments can be understood in more detail from the followingdescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a cross-sectional view of a light emitting device package inaccordance with an embodiment;

FIG. 2 is an enlarged view of a portion A of FIG. 1;

FIG. 3 is a plan view illustrating an example of the light emittingdevice package of FIG. 1;

FIG. 4 is an enlarged view of a guide member of FIG. 3;

FIG. 5 is a perspective view illustrating an example of the guide memberof FIG. 1;

FIGS. 6 to 8 are cross-sectional views illustrating a process ofaligning a light incident part of a lens by using the guide member ofFIG. 1;

FIG. 9 is a cross-sectional view illustrating another example of thelight emitting device package of FIG. 1;

FIG. 10 is a plan view illustrating another example of the lightemitting device package of FIG. 1;

FIG. 11 is a cross-sectional view of a light emitting device package inaccordance with another embodiment;

FIG. 12 is a cross-sectional view of a backlight unit in accordance withan embodiment;

FIG. 13 is a cross-sectional view of a light emitting device package inaccordance with an embodiment or another embodiment;

FIG. 14 is an enlarged view of a portion A of FIG. 13;

FIG. 15 is a plan view illustrating an example of the light emittingdevice package of FIG. 13;

FIG. 16 is a perspective view illustrating an example of a guide memberof FIG. 13;

FIGS. 17 to 19 are cross-sectional views illustrating a process ofaligning a light incident part of a lens by using the guide member ofFIG. 13;

FIG. 20 is a cross-sectional view illustrating another example of thelight emitting device package of FIG. 13;

FIG. 21 is a cross-sectional view of a light emitting device package inaccordance with an embodiment or another embodiment;

FIG. 22 is a cross-sectional view of a backlight unit in accordance withanother embodiment;

FIG. 23 is a cross-sectional view of a light emitting device package inaccordance with an embodiment or another embodiment;

FIG. 24 is an enlarged view of a portion A of FIG. 23;

FIG. 25 is a plan view illustrating an example of the light emittingdevice package of FIG. 23;

FIG. 26 is a perspective view illustrating an example of a guide memberof FIG. 23;

FIG. 27 is a plan view illustrating another example of an encapsulationmaterial of FIG. 23;

FIGS. 28 to 30 are cross-sectional views illustrating a process ofaligning a light incident part of a lens by using the guide member ofFIG. 23;

FIG. 31 is a cross-sectional view of a light emitting device package inaccordance with an embodiment or another embodiment;

FIG. 32 is a cross-sectional view of a light emitting device package inaccordance with an embodiment or another embodiment; and

FIG. 33 is a cross-sectional view of a backlight unit in accordance withan embodiment or another embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter, several embodiments of the present disclosure will bedescribed in detail with reference to the accompanying drawings.

The embodiments of the present disclosure are provided to more fullydescribe the present disclosure to those of ordinary skill in the art.The following embodiments may be modified to various types and the scopeof the present disclosure is not limited to the following embodiments.Rather, these embodiments are provided so that this disclosure will bethorough and complete, and will fully convey the spirit of the presentdisclosure to those skilled in the art. Also, in the figures, athickness or dimension of each of layers is exaggerated for clarity ofillustration.

It will be understood that it is referred to as being “on,” “connectedto”, “stacked”, or “coupled to” another element, it may be directly on,connected, stacked, or coupled to the other element or interveningelements may be present. In contrast, when an element is referred to asbeing “directly on,” “directly connected to” or “directly coupled to”another element or layer, there are no intervening elements or layerspresent. Like reference numerals refer to like elements throughout. Asused herein, the term “and/or” includes any and all combinations of oneor more of the associated listed items.

As used herein, terms such as “first,” “second,” etc. are used todescribe various members, components, regions, layers, and/or portions.However, it is obvious that the members, components, regions, layers,and/or portions should not be defined by these terms. The terms do notmean a particular order, up and down, or superiority, and are used onlyfor distinguishing one member, component, region, layer, or portion fromanother member, component, region, layer, or portion. Thus, a firstmember, component, region, layer, or portion which will be described mayalso refer to a second member, component, region, layer, or portion,without departing from the teaching of the present disclosure.

Spatially relative terms, such as “above” or “upper” and “below” or“lower” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the term “above” may encompass both an orientation of above andbelow. The device may be otherwise oriented (rotated at 90 degrees or atother orientations) and the spatially relative descriptors used hereinwill be interpreted accordingly.

The terms used herein are for illustrative purposes of the presentdisclosure only and should not be construed to limit the meaning or thescope of the present disclosure. As used in this specification, asingular form may, unless definitely indicating a particular case interms of the context, include a plural form. Also, the expressions“comprise” and/or “comprising” used in this specification neither definethe mentioned shapes, numbers, steps, operations, members, elements,and/or groups of these, nor exclude the presence or addition of one ormore other different shapes, numbers, steps, operations, members,elements, and/or groups of these, or addition of these. The term“and/or” used herein includes any and all combinations of one or more ofthe associated listed items.

Hereinafter, embodiments of the present disclosure will be describedwith reference to the attached drawings that schematically illustratethe ideal embodiments of the present disclosure. In the drawings, forexample, according to the manufacturing technology and/or tolerance, themodification of the illustrated shape may be expected. Thus, theembodiments of the present disclosure must not be interpreted to belimited by a particular shape that is illustrated in the drawings andmust include a change in the shape occurring, for example, duringmanufacturing.

FIG. 1 is a cross-sectional view of a light emitting device package inaccordance with an embodiment, FIG. 2 is an enlarged view of a portion Aof FIG. 1, FIG. 3 is a plan view illustrating an example of the lightemitting device package of FIG. 1, FIG. 4 is an enlarged view of a guidemember of FIG. 3, and FIG. 5 is a perspective view illustrating anexample of the guide member of FIG. 1.

Referring to FIGS. 1 to 5, a light emitting device package 100 inaccordance with an embodiment may include a substrate 10, a lightemitting device 20, an encapsulation material 30, and a guide member 50.

Here, the light emitting device 20 may be mounted on and electricallyconnected to the substrate 10. Thus, the substrate 10 may be formed of aconductive material having proper mechanical strength and insulation tosupport the light emitting device 20.

For example, the substrate 10 may be a printed circuit board (PCB) onwhich various wiring layers for connecting the light emitting device 20to an external power source are formed and which is multilayered byusing an epoxy-based resin sheet. Also, the substrate 10 may be aflexible PCB formed of a soft material.

Alternatively, the substrate 10 may be a synthetic resin substrate suchas a resin, glass epoxy, etc., or a ceramic substrate in considerationof thermal conductivity. In addition, the substrate 10 may be aninsulated metallic substrate such as aluminum, copper, zinc, tin, lead,gold, silver, or the like. Also, the substrate 10 may be a plate-shapedor lead frame-shaped substrate.

Also, the light emitting device 20 may be seated on the substrate 10. InFIG. 1, the substrate 10 on which one light emitting device 20 is seatedis illustrated as an example.

Alternatively, a plurality of light emitting devices 20 may be seated onthe substrate 10.

The light emitting device 20 may comprise a semiconductor. For example,the light emitting device 20 may include a blue, green, red, or yellowLEDs comprising a nitride semiconductor or an ultraviolet (UV) LED. Thenitride semiconductor may have a composition formula ofAl_(x)Ga_(y)In_(z)N (0≦x≦1, 0≦y≦1, 0≦z≦1, x+y+z=1).

Also, the light emitting device 20 may be formed by epitaxial growingthe nitride semiconductor such as InN, AlN, InGaN, AlGaN, or InGaAlN ona growth sapphire substrate or silicon carbide substrate through vapordeposition, for example, metal organic chemical vapor deposition(MOCVD). Also, the light emitting device 20 may be formed by using asemiconductor such as ZnO, ZnS, ZnSe, SiC, GaP, GaAlAs, or AlInGaP inaddition to the nitride semiconductor. The semiconductor may be formedby using a stacked body including an n-type semiconductor layer, a lightemitting layer, and a p-type semiconductor layer, which are successivelystacked. The light emitting layer (an active layer) may be formed byusing a stacked semiconductor having a multi quantum well (MQW)structure or a single quantum well structure or a stacked semiconductorhaving a double hetero structure. Also, the light emitting device 20 mayselectively emit light having a predetermined wavelength according to ause of a display or lighting.

Here, an insulation, conductive, or semiconductor substrate may be usedas the growth substrate if necessary. For example, the growth substratemay be formed of sapphire, SiC, Si, MgAl₂O4, MgO, LiAlO₂, LiGaO₂, orGaN. For example, to epi-grow a GaN material, the GaN substrate that isa homo structure may be used. However, the GaN substrate may havedifficulty in manufacture and have high production costs.

Thus, the sapphire or silicon carbide (SiC) substrate that is a heterosubstrate may be mainly used. Here, the sapphire substrate may be morewidely used instead of the SiC substrate that is relatively high inprice. When the hetero substrate is used, a defect such as dislocationdue to a lattice constant between a substrate material and a thin filmmaterial may increase. Also, when a temperature changes, substratewarpage may occur due to a difference in thermal expansion coefficientbetween the substrate material and the thin film material to causecracks in a thin film. Here, the occurrence of the above-describedlimitation may be reduced by using a buffer layer disposed between thesubstrate 10 and a GaN-based light emitting stacked body S.

Also, the growth substrate may be completely or partially removed orpatterned during a chip manufacturing process to improve light orelectrical characteristics of the LED chip before or after being grownto an LED structure.

For example, in the case of the sapphire substrate, laser may beirradiated onto an interface between the substrate and the semiconductorlayer to separate the substrate from the semiconductor layer. Also, thesilicon or silicon carbide substrate may be reduced through apolishing/etching process.

Also, when the growth substrate is removed, the other substrate may beused. A support substrate may be bonded by using a reflection metal, ora reflection structure may be inserted into a center of the bondinglayer to improve light efficiency of the LED chip disposed at a sideopposite to the original growth substrate.

Also, the growth substrate may be patterned to form an unevenness orinclined surface on a main surface (a surface or both side surfaces) orside surface of the substrate before or after being grown to the LEDstructure, thereby improving light extraction efficiency. The patternmay have a size of about 5 nm to about 500 μm. Here, the pattern may beregularly or irregularly formed to improve the light extractionefficiency. Also, the pattern may have various shapes such as pillar,mountain, hemispherical, and polygonal shapes.

The sapphire substrate may be formed of a crystal having Hexa-Rhombo R3csymmetry. The sapphire substrate may have a lattice constant of 13.001 Åalong a C-axis and a lattice constant of 4.758 Å along an A-axis. Also,orientation planes of the sapphire substrate may include a C(0001)plane, an A(1120) plane, an R(1102) plane, and the like. In this case,the C(0001) plane is mainly used as a nitride growth substrate becauseit relatively facilitates the growth of a nitride film and is stable ata high temperature.

Also, the Si substrate may be exemplified as another example of thegrowth substrate. The Si substrate may be suitable for large-sizedsubstrates and have a relatively low price to improve mass production.There is a demand for establishment of a technology to suppress anoccurrence of crystal defects due to a difference in lattice constant ofabout 17% between the Si substrate having a plane (111) and GaN. Also,there is a demand for establishment of a technology to suppress thewafer warpage that occurs due to a difference in thermal expansion rateof about 56% between Si and GaN. The cracks in the GaN thin film mayoccur due to the wafer warpage. Also, the process control may bedifficult to cause a limitation in which dispersion in light emittingwavelength within the same wafer increases.

Also, since the Si substrate absorbs light emitted from the GaN-basedsemiconductor to reduce external quantum efficiency of the lightemitting device, the substrate may be removed as occasion demands, and asupport substrate such as Si, Ge, SiAl, ceramic, or metal substrateincluding a reflection layer may be additionally formed.

When the GaN thin film is grown on the hetero substrate such as the Sisubstrate, dislocation density may increase due to mismatch in latticeconstant between the substrate material and the thin film material, andthe cracks and warpage may occur due to a difference in thermalexpansion coefficient between the substrate material and the thin filmmaterial. To prevent the dislocation and cracks of the light emittingstacked body, a buffer layer may be disposed between the growthsubstrate and the light emitting stacked body. The buffer layer mayadjust a bent degree of the substrate when the active layer is grown toreduce the wavelength dispersion of the wafer.

Here, the buffer layer may be formed of a semiconductor material havinga compositional formula of Al_(x)In_(y)Ga_(1-x-y)N (0≦x≦1, 0≦y≦1,x+y≦1), particularly, GaN, AlN, AlGaN, InGaN, or InGaNAlN. As occasiondemands, the buffer layer may be formed of a material such as ZrB₂,HfB₂, ZrN, HfN, or TiN. Also, a plurality of layers may be combined witheach other to form the buffer layer, or the composition of the bufferlayer may gradually change.

Also, although not shown, the light emitting device 20 may include aflip chip-shaped light emitting device having a signal transmissionmedium such as a bump, pad, or solder. Alternatively, the light emittingdevice 20 may include various light emitting devices such as verticaltype and horizontal type light emitting devices having a signaltransmission medium such as a wire.

Also, the encapsulation material 30 may be disposed on the substrate 10and have a through-hole to surround the light emitting device 20. Asillustrated in FIG. 3, the through-hole of the encapsulation material 30may have, for example, a circular shape. In addition, the through-holemay have various shapes such as a quadrangular shape, an oval shape, apolygonal shape, a trapezoid shape, and a combined shape.

Also, the encapsulation material 30 may be formed of at least onematerial selected from an epoxy molding compound (EMC), an EMCcontaining at least reflection material, white silicon containing areflection material, a photo solder resister (PSR), and a combinationthereof.

Also, the encapsulation material 30 may be molded, dispensed, orscreen-printed on the substrate 10.

More particularly, for example, the encapsulation material 30 may beformed of an epoxy resin composition, a silicon resin composition, amodified epoxy resin composition such as a silicone modified epoxy resincomposition, a modified silicon resin composition such as an epoxymodified silicon resin, a polyimide resin composition, a modifiedpolyimide resin composition, or a resin such as polyphthalamide (PPA), apolycarbonate resin, poly(phenylene sulfide) (PPS), a liquid crystalpolymer (LCP), an ABS resin, a phenol resin, an acrylic resin, and a PBTresin.

Also, titanium oxide, silicon dioxide, titanium dioxide, zirconiumdioxide, potassium titanate, alumina, aluminum nitride, boron nitride,mullite, chrome, or a light reflective material such as a white-based ormetal-based component may be contained in the resin.

As illustrated in FIG. 9, the encapsulation material 30 may have variousshapes. Thus, the shape of the encapsulation material 30 of the lightemitting device package 100 in accordance with an embodiment is notlimited to that illustrated in FIG. 1.

The guide member 50 may be disposed on the encapsulation member 30 toguide an assembly path of a lens 40. The guide member 50 may include afirst inclined surface 51, a second inclined surface 52, a contactsurface 53, a top surface 54, a bottom surface 55, and a stopper 56.

Here, as illustrated in FIG. 2, the first inclined surface 51 is aportion having a relatively gentle inclination to guide a light incidentpart 40 a of the lens 40.

Also, the second inclined surface 52 is continuously disposed on thefirst inclined surface 51 to further guide the light incident part 40 aof the lens 40 and has a second inclination steeper than that of thefirst inclination.

Also, the contact surface 53 is continuously disposed on the secondinclined surface 52 to finally contact and be fixed to the lightincident part 40 a of the lens 40, i.e., an inner engaging surface 42′of the lens 40. Thus, the contact surface 53 may have a contact portion.Here, the contact surface 53 may have an inclined angle of about 90°with respect to an assembly direction toward the lens 40. The lens 40may have an engaging surface and the inner engaging surface 42′ is oneexample of the engaging surface.

The top surface 54 is a flat portion at which the first inclined surface51 starts, and the bottom surface 55 is a portion at which the contactsurface 53 is ended.

Here, the bottom surface 55 may have an area greater than that of thetop surface 54. As illustrated in FIGS. 1 to 5, for example, the guidemember 50 of the light emitting device package 100 in accordance with anembodiment may generally have a wide lower portion and a narrow upperportion.

Also, as illustrated in FIG. 2, the first inclined surface 51 may havean inclined internal angle K1 of about 100° to about 135° with respectto the top surface 54, the second inclined surface 52 may have aninclined internal angle K2 of about 150° to about 175° with respect tothe first inclined surface 51, and the contact surface 53 may have aninclined internal angle K3 greater than at least the inclined internalangle K2 with respect to the second inclined surface 52 so that theguide member 50 guides the light incident part 40 a of the lens 40 in aprimarily gentile inclined direction and then in a secondarilysignificantly inclined direction when the light incident part 40 a ofthe lens 40 is guided.

Also, as illustrated in FIG. 2, a edge R1 between the top surface 54 andthe first inclined surface 51 and a edge R2 between the first inclinedsurface 51 and the second inclined surface 52 may be roundly chamferedto prevent the component from being damaged when the light incident part40 a of the lens 40 collides with the components.

Also, as illustrated in FIG. 2, the stopper 56 may be connected to thecontact surface 53 and be in contact with a bottom surface or a bottomengaging surface 42 of the light incident part 40 a of the lens 40.Thus, the stopper 56 may determine an assembly position of the lightincident part 40 a of the lens 40.

Also, as illustrated in FIG. 3, three guide members 50 may be integrallymolded with the encapsulation material 30 to protrude in a directiontoward the lens 40.

Alternatively, at least two guide members 50 may be integrally moldedwith the encapsulation material 30 to protrude in the direction towardthe lens 40. Also, as illustrated in FIG. 10, four guide members 50 maybe integrally molded with the encapsulation material 30 to protrude inthe direction toward the lens 40.

Also, as illustrated in FIG. 4, to minimize light interference, a shadowphenomenon, and a shadow overlapping phenomenon, an outer surface of theguide member 50 may be partially rounded to correspond to an arc shapeof an inlet of the incident part 40 a of the lens 40. The top surface 54may have an outer width L1 of about 400 micrometers to about 700micrometers and an inner width L2 of about 200 micrometers to about 450micrometers. Also, the bottom surface 55 may have an outer width L3 ofabout 30 micrometers to about 1,200 micrometers and an inner width L4 ofabout 500 micrometers to about 700 micrometers. Also, a side surface 58of the guide member 50 may have an inclined angle K4 that is not greaterthan 20° (greater than 0°).

Also, the guide member 50 may comprise at least one material selectedfrom the group consisting of an epoxy molding compound (EMC), an EMCcontaining at least reflection material, white silicon containing areflection material, a photo solder resister (PSR), and a combinationthereof.

Also, the guide member 50 may be molded, dispensed, or screen-printed onthe substrate 10.

More particularly, for example, the guide member 50 may be formed of anepoxy resin composition, a silicon resin composition, a modified epoxyresin composition such as a silicone modified epoxy resin composition, amodified silicon resin composition such as an epoxy modified siliconresin, a polyimide resin composition, a modified polyimide resincomposition, or a resin such as polyphthalamide (PPA), a polycarbonateresin, poly(phenylene sulfide) (PPS), a liquid crystal polymer (LCP), anABS resin, a phenol resin, an acrylic resin, and a PBT resin.

Also, titanium oxide, silicon dioxide, titanium dioxide, zirconiumdioxide, potassium titanate, alumina, aluminum nitride, boron nitride,mullite, chrome, or a light reflective material such as a white-based ormetal-based component may be contained in the resin.

The guide member 50 may be formed of the same material as theencapsulation material 30 or formed of a material different from theencapsulation material 30. The different material may representmaterials that are not absolutely identical to each other.

As illustrated in FIG. 1, the light emitting device package 100 inaccordance with an embodiment may further include the lens 40 of which aportion of an inner surface of the light incident part 40 a (an innerengaging surface 42′) contacts the guide member 50, and on which a fixedpart 41 fixed to the substrate 10 is disposed.

FIGS. 6 to 8 are cross-sectional views illustrating a process ofaligning the light incident part 40 a of the lens 40 by using the guidemember 50 of FIG. 1.

Explaining the process of aligning the lens of the light emitting devicepackage 100 in accordance with an embodiment in more detail inmulti-stages, as illustrated in FIG. 6, the light incident part 40 a ofthe lens 40 may be guided along the first inclined surface 51 of theguide member 50. Here, the light incident part 40 a of the lens 40 maymove along the top surface 54 and then be macroscopically guided firstby the first inclined surface 51 of the guide member 50.

Then, as illustrated in FIG. 7, the light incident part 40 a of the lens40 may be guided along the second inclined surface 52 of the guidemember 50. Here, while the light incident part 40 a is finely guided bythe second inclined surface 52, the light incident part 40 a of the lens40 may be finely aligned to balance forces of other light incident parts40 a that are disposed at a side opposite to the light incident part 40a.

For example, when the light incident part 40 a disposed at one side ofthe lens 40 enters into the second inclined surface 52, the lightincident parts 40 a disposed at the other side of the lens 40 may alsoenter into the second inclined surface 52 to balance the forcestherebetween.

That is, the first inclined surface 51 may align a macroscopic positionof the lens 40, and the second inclined surface 52 may finely align thelens 40 to balance the lens 40.

Then, as illustrated in FIG. 8, the light incident part 40 a of the lens40 may finally contact the contact surface 53 and be guided along thecontact surface 53. Then, when the bottom surface of the light incidentpart 40 a reaches the stopper 56, the lens 40 may be aligned in a properposition.

Thus, the lens 40 may be easily aligned by using the guide member 50 andbe improved in assembly accuracy to prevent luminance and colordeviations of a display device, improve light characteristics, andproduce high-quality products. Therefore, since the lens 40 is alignedin multi-stages by using the first inclined surface 51, the secondinclined surface 52, the contact surface 53, and the stopper 56, thedamage of the lens 40 may be prevented, and alignment accuracy of thelens 40 may be improved.

FIG. 11 is a cross-sectional view of a light emitting device package inaccordance with another embodiment.

Referring to FIG. 11, a light emitting device package 200 in accordancewith another embodiment may further include a hook surface 57 disposedon the contact surface 53 so that the hook surface 57 is engaged with ahook part 43 disposed on a light incident part 40 a of a lens 40.

Thus, the light incident part 40 a of the lens 40 is hooked on the hooksurface 57 to more firmly couple the lens 40 to an encapsulationmaterial 30. Also, it may easily confirm the state in which the lens 40and the encapsulation material 30 are completely aligned with each otherby using the “clack” feel or sound when the lens 40 and theencapsulation material 30 are assembled with each other.

Here, although the hook part 43 and the hook surface 57 are respectivelydisposed on the light incident part 40 a of the lens 40 and the contactsurface 53, the present disclosure is not limited thereto. For example,the hook part 43 and the hook surface 57 may be disposed on the contactsurface 53 and the light incident part 40 a of the lens 40,respectively.

Also, although not shown, a phosphor may be disposed around a lightemitting device 20. For example, the phosphor may have followingcomposition formula and color.

Oxide-based: yellow and green Y₃Al₅O₁₂:Ce, Tb₃A₁₅O₁₂:Ce, andLu₃Al₅O₁₂:Ce

Silicate-based: yellow and green (Ba,Sr)₂SiO₄:Eu, and yellow and orange(Ba,Sr)₃SiO₅:Ce

Nitride-based: green β-SiAlON:Eu, yellow L₃Si₆O₁₁:Ce, orangeα-SiAlON:Eu, and red CaAlSiN₃:Eu, Sr₂Si₅N₈:Eu, and SrSiAl₄N₇:Eu

The composition of the phosphor may basically accord with stoichiometry.Also, each of elements may be substituted for the other element withineach of the groups in the periodic table. For example, Sr may besubstituted for Ba, Ca, Mg, and the like in the alkali (II) group, andlanthanum-based Tb, Lu, Sc, Gd, and the like. Also, Eu that is an activeagent may be substituted for Ce, Tb, Pr, Er, Yb, and the like accordingto a desired energy level. Here, the active agent may be applied alone,or an additional active agent for modifying properties thereof may beadditionally applied.

Also, a material such as quantum dot (QD) may be applied as a materialsubstituted for the phosphor. Alternatively, the phosphor and QD may bemixed with the LED, or each of the phosphor and the QD may be usedalone.

The QD may be constituted by a core formed of CdSe, InP, and the like, ashell (about 0.5 nm to about 2 nm) formed of ZnS, ZnSe, and the like,and a regand for stabilizing the shell. The QD may realize variouscolors according to a size thereof.

Also, the phosphor or quantum dot may be applied to the LED chip orlight emitting device by being sprayed, covered in a film shape, orattached in a sheet shape such as a film or ceramic phosphor.

The spraying method may generally include dispensing and spray coatingmethods. Here, the dispensing method may include a pneumatic method anda screw or linear type mechanical method. In addition, a small amount ofphosphor or quantum dot may be discharged by using a jetting method tocontrol a dotted amount, and also, a color coordinate may be controlledthrough the dotted amount control. The method of spraying the phosphorin a lump on a wafer level or light emitting device substrate may beeasy in productivity and thickness control.

The method of directly covering the film on the light emitting device orLED chip may include an electrophoresis, screen printing, or a phosphormolding method. That is, the above-described methods may vary accordingto whether a side surface of the LED chip is coated.

To control efficiency of the light emitting phosphor having a longwavelength, which re-absorbs light having a short wavelength, of atleast two kinds of phosphors having light emitting wavelengths differentfrom each other, the at least two kinds of phosphors having the lightemitting wavelengths different from each other may be distinguished fromeach other. To minimize the re-absorption and interference of the LEDchip and the at least two kinds of phosphors, a DBR (ODR) layer may bedisposed between each of the layers.

Also, to form a uniform coating layer, the phosphor may be formed in afilm or ceramic shape and then be attached to the LED chip or lightemitting device.

A light conversion material may be located at a remote position to causea difference in light efficiency and light distribution characteristics.Here, the light conversion material may be located together with lighttransmission polymer or glass according to durability andheat-resistance thereof.

As described above, since the phosphor coating technology plays a largerole in determining the light characteristics of the light emittingdevice, technologies for controlling a thickness of the phosphor coatinglayer and the uniform dispersion of the phosphor are being variouslystudied. Like the phosphor, the QD may also be located at the LED chipor light emitting device. Also, the QD may be disposed between the glassor light transmission polymer materials to convert light.

FIG. 12 is a cross-sectional view of a backlight unit in accordance withembodiments.

Referring to FIG. 12, a backlight unit in accordance with an embodimentmay largely include a substrate 10, a light emitting device 20, anencapsulation material 30, a guide member 50, and a light guide plate60.

Here, the backlight unit may be disposed on an LCD panel to transmitlight toward the LCD panel. The light emitting device 20, theencapsulation material 30, and the guide member 50 may have the sameconstitution and effect as those described with reference to FIGS. 1 to5.

The light guide plate 60 may be disposed in a path of light emitted fromthe light emitting device 20 to transmit the light emitted from thelight emitting device 20 into a wider area. The light guide plate 60 maybe formed of a polycarbonate-based resin, a polysulfone-based resin, apolyacrylate-based resin, a polystyrene-based resin, a polyvinylchloride-based resin, a polyvinyl alcohol-based resin, apolynorbornene-based resin, or a polyester-based resin. In addition, thelight guide plate 60 may be formed of various light transmission resinmaterials. Also, a fine pattern, a fine protrusion, or a diffusion layermay be formed on a surface of the light guide plate 60, or microbubblesmay be formed in the light guide plate 60.

The backlight unit in accordance with an embodiment may be a direct-typebacklight unit in which the light emitting device 20 is disposed underthe light guide plate 60.

FIG. 13 is a cross-sectional view of a light emitting device package inaccordance with an embodiment or another embodiment, FIG. 14 is anenlarged view of a portion A of FIG. 13, FIG. 15 is a plan viewillustrating an example of the light emitting device package of FIG. 13,and FIG. 16 is a perspective view illustrating an example of a guidemember of FIG. 13.

Referring to FIGS. 13 to 16, a light emitting device package 300 inaccordance with an embodiment or another embodiment may largely includea substrate 10, a light emitting device 20, an encapsulation material30, and a guide member 50.

Here, the substrate 10 and the light emitting device 20 may have thesame constitution and effect as those of the light emitting devicepackage 100 in accordance with the embodiment that is described withreference to FIGS. 1 to 12. Thus, detailed descriptions thereof will beomitted.

Also, the encapsulation material 30 may be disposed on the substrate 10and have a through-hole to surround the light emitting device 20. Asillustrated in FIG. 15, the through-hole of the encapsulation material30 may have, for example, a circular shape. In addition, thethrough-hole may have various shapes such as a quadrangular shape, anoval shape, a polygonal shape, a trapezoid shape, and a combined shape.

Also, the encapsulation material 30 may be formed of at least onematerial selected from an epoxy molding compound (EMC), an EMCcontaining at least reflection material, white silicon containing areflection material, a photo solder resister (PSR), and a combinationthereof.

Also, the encapsulation material 30 may be molded, dispensed, orscreen-printed on the substrate 10 in a quadrangular plate shape asillustrated in FIG. 15.

More particularly, for example, the encapsulation material 30 may beformed of an epoxy resin composition, a silicon resin composition, amodified epoxy resin composition such as a silicone modified epoxy resincomposition, a modified silicon resin composition such as an epoxymodified silicon resin, a polyimide resin composition, a modifiedpolyimide resin composition, or a resin such as polyphthalamide (PPA), apolycarbonate resin, poly(phenylene sulfide) (PPS), a liquid crystalpolymer (LCP), an ABS resin, a phenol resin, an acrylic resin, and a PBTresin.

Also, titanium oxide, silicon dioxide, titanium dioxide, zirconiumdioxide, potassium titanate, alumina, aluminum nitride, boron nitride,mullite, chrome, or a reflective material such as a white-based ormetal-based component may be contained in the resin.

As illustrated in FIG. 20, the encapsulation material 30 may havevarious shapes. Thus, the shape of the encapsulation material 30 of thelight emitting device package 300 in accordance with an embodiment oranother embodiment is not limited to that illustrated in FIG. 13.

The guide member 50 may be disposed on each of four edges of theencapsulation member 30 to guide an assembly path of a lens 40. Asillustrated in FIG. 14, the guide member 50 may include a first inclinedsurface 51, a second inclined surface 52, a contact surface 53, a topsurface 54, a bottom surface 55, and a stopper 56.

Here, as illustrated in FIG. 14, the first inclined surface 51 may be aportion having a relatively gentile inclination to primarily block alight incident part 40 a of the lens 40.

Also, the second inclined surface 52 may be continuously disposed on thefirst inclined surface 51 to secondarily guide the light incident part40 a of the lens 40 and have a second inclination relatively greaterthan that of the first inclination.

Also, the contact surface 53 may be continuously disposed on the secondinclined surface 52 to finally contact and be fixed to the lightincident part 40 a of the lens 40. Thus, the contact surface 53 may havea contact portion. Here, the contact surface 53 may have an inclinedangle of about 90° with respect to an assembly direction toward the lens40.

The top surface 54 may be a flat portion at which the first inclinedsurface 51 starts, and the bottom surface 55 may be a portion at whichthe contact surface 53 is ended.

Here, the bottom surface 55 may have an area greater than that of thetop surface 54. As illustrated in FIGS. 13 to 16, for example, the guidemember 50 of the light emitting device package 300 in accordance with anembodiment or another embodiment may generally have a wide lower portionand a narrow upper portion.

Also, as illustrated in FIG. 14, the first inclined surface 51 may havean inclined internal angle K1 of about 100° to about 135° with respectto the top surface 54, the second inclined surface 52 may have aninclined internal angle K2 of about 150° to about 175° with respect tothe first inclined surface 51, and the contact surface 53 may have aninclined internal angle K3 greater than at least the inclined internalangle K2 with respect to the second inclined surface 52 so that theguide member 50 guides the light incident part 40 a of the lens 40 in aprimarily gentile inclined direction and then in a secondarilysignificantly inclined direction when the light incident part 40 a ofthe lens 40 is guided.

Also, as illustrated in FIG. 14, an edge R1 between the top surface 54and the first inclined surface 51 and an edge R2 between the firstinclined surface 51 and the second inclined surface 52 may be roundlychamfered to prevent the component from being damaged when the lightincident part 40 a of the lens 40 collides with the components.

Also, as illustrated in FIG. 14, the stopper 56 may be connected to thecontact surface 53 and be in contact with a bottom surface 42 of thelight incident part 40 a of the lens 40. Thus, the stopper 56 maydetermine an assembly position of the light incident part 40 a of thelens 40. Selectively, a top surface of the stopper 56 may be disposedlower than the bottom surface 55 to seat the lens 40 thereon.

Also, as illustrated in FIG. 15, the encapsulation material 30 may havea substantially quadrangular plate shape. The guide member 50 may beintegrally molded with the encapsulation material 30 so that four guidemembers 50 protrude from four corners of the encapsulation material 50toward the lens 40.

The guide member 50 may be integrally molded with the encapsulationmaterial 30 so that at least fourteen guide members 50 protrude in thedirection toward the lens 40.

Also, as illustrated in FIG. 16, a side surface 58 of the guide member50 may have an inclined angle K4 of about 45° or less.

Also, the guide member 50 may be formed of at least one materialselected from an epoxy molding compound (EMC), an EMC containing atleast reflection material, white silicon containing a reflectionmaterial, a photo solder resister (PSR), and a combination thereof.

Also, the guide member 50 may be molded, dispensed, or screen-printed onthe substrate 10.

More particularly, for example, the guide member 50 may be formed of anepoxy resin composition, a silicon resin composition, a modified epoxyresin composition such as a silicone modified epoxy resin composition, amodified silicon resin composition such as an epoxy modified siliconresin, a polyimide resin composition, a modified polyimide resincomposition, or a resin such as polyphthalamide (PPA), a polycarbonateresin, poly(phenylene sulfide) (PPS), a liquid crystal polymer (LCP), anABS resin, a phenol resin, an acrylic resin, and a PBT resin.

Also, titanium oxide, silicon dioxide, titanium dioxide, zirconiumdioxide, potassium titanate, alumina, aluminum nitride, boron nitride,mullite, chrome, or a reflective material such as a white-based ormetal-based component may be contained in the resin.

The guide member 50 may be formed of the same material as theencapsulation material 30 or formed of a material different from theencapsulation material 30. The different material may representmaterials that are not absolutely identical to each other.

Although not shown, the guide member 50 may not protrude in thedirection toward the lens 40, and the first inclined surface 51, thesecond inclined surface 52, and the contact surface 53 of the guidemember 50 may be disposed on a side surface of an edge of theencapsulation material 30. Also, the stopper 56 may be omitted.

As illustrated in FIG. 13, the light emitting device package 300 inaccordance with an embodiment may further include the lens 40 of which aportion of an inner surface of the light incident part 40 a contacts theguide member 50, and on which a fixed part 41 fixed to the substrate 10is disposed.

FIGS. 17 to 19 are cross-sectional views illustrating a process ofaligning a light incident part 40 a of a lens 40 by using the guidemember 50 of FIG. 13.

Explaining the process of aligning the lens of the light emitting devicepackage 300 in accordance with an embodiment or another embodiment inmore detail in stages, as illustrated in FIG. 17, the light incidentpart 40 a of the lens 40 may be guided along the first inclined surface51 of the guide member 50. Here, the light incident part 40 a of thelens 40 may move along the top surface 54 and then be macroscopicallyguided first by the first inclined surface 51 of the guide member 50.

Then, as illustrated in FIG. 18, the light incident part 40 a of thelens 40 may be guided along the second inclined surface 52 of the guidemember 50. Here, while the light incident part 40 a is finely guided bythe second inclined surface 52, the light incident part 40 a of the lens40 may be finely aligned to balance forces of other light incident parts40 a that are disposed at a side opposite to the light incident part 40a.

For example, when the light incident part 40 a disposed at one side ofthe lens 40 enters into the second inclined surface 52, the lightincident parts 40 a disposed at the other side of the lens 40 may alsoenter into the second inclined surface 52 to balance the forcestherebetween.

That is, the first inclined surface 51 may align a macroscopic positionof the lens 40, and the second inclined surface 52 may finely align thelens 40 to balance the lens 40.

Then, as illustrated in FIG. 19, the light incident part 40 a of thelens 40 may finally contact the contact surface 53 and be guided alongthe contact surface 53. Then, when the bottom surface of the lightincident part 40 a reaches the stopper 56, the lens 40 may be aligned ina proper position.

Thus, the lens 40 may be easily aligned by using the guide member 50 andbe improved in assembly accuracy to prevent luminance and colordeviations of a display device, improve light characteristics, andproduce high-quality products. Therefore, since the lens 40 is alignedin multi-stages by using the first inclined surface 51, the secondinclined surface 52, the contact surface 53, and the stopper 56, thedamage of the lens 40 may be prevented, and alignment accuracy of thelens 40 may be improved.

FIG. 21 is a cross-sectional view of a light emitting device package 400in accordance with an embodiment or another embodiment.

Referring to FIG. 21, a light emitting device package 400 in accordancewith another embodiment may further include a hook surface 57 disposedon the contact surface 53 so that the hook surface 57 is engaged with ahook part 43 disposed on a light incident part 40 a of a lens 40.

Thus, the light incident part 40 a of the lens 40 is hooked on the hooksurface 57 to more firmly couple the lens 40 to an encapsulationmaterial 30. Also, it may easily confirm the state in which the lens 40and the encapsulation material 30 are completely aligned with each otherby using the “clack” feel or sound when the lens 40 and theencapsulation material 30 are assembled with each other.

Here, although the hook part 43 and the hook surface 57 are respectivelydisposed on the light incident part 40 a of the lens 40 and the contactsurface 53, the present disclosure is not limited thereto. For example,the hook part 43 and the hook surface 57 may be disposed on the contactsurface 53 and the light incident part 40 a of the lens 40,respectively.

Also, although not shown, a phosphor may be disposed around a lightemitting device 20. FIG. 22 is a cross-sectional view of a backlightunit in accordance with another embodiment.

Referring to FIG. 22, a backlight unit in accordance with anotherembodiment may largely include a substrate 10, a light emitting device20, an encapsulation material 30, a guide member 50, and a light guideplate 60.

Here, the backlight unit may be disposed on an LCD panel to transmitlight toward the LCD panel. The light emitting device 20, theencapsulation material 30, and the guide member 50 may have the sameconstitution and effect as those described with reference to FIGS. 13 to17.

The light guide plate 60 may be disposed in a path of light emitted fromthe light emitting device 20 to transmit the light emitted from thelight emitting device 20 into a wider area. The light guide plate 60 maybe formed of a polycarbonate-based resin, a polysulfone-based resin, apolyacrylate-based resin, a polystyrene-based resin, a polyvinylchloride-based resin, a polyvinyl alcohol-based resin, apolynorbornene-based resin, or a polyester-based resin. In addition, thelight guide plate 60 may be formed of various light transmission resinmaterials. Also, a fine pattern, a fine protrusion, or a diffusion layermay be formed on a surface of the light guide plate 60, or microbubblesmay be formed in the light guide plate 60.

The backlight unit in accordance with another embodiment may be adirect-type backlight unit in which the light emitting device 20 isdisposed under the light guide plate 60.

FIG. 23 is a cross-sectional view of a light emitting device package 500in accordance with an embodiment or another embodiment, FIG. 24 is anenlarged view of a portion A of FIG. 23, FIG. 25 is a plan viewillustrating an example of the light emitting device package 500 of FIG.23, and FIG. 26 is a perspective view illustrating an example of a guidemember 30-1 of FIG. 23.

Referring to FIGS. 23 to 26, a light emitting device package 500 inaccordance with an embodiment or another embodiment may largely includea substrate 10, a light emitting device 20, an encapsulation material30, and a guide member 30-1.

Here, the substrate 10 and the light emitting device 20 may have thesame constitution and effect as those of the light emitting devicepackage 100 in accordance with the embodiment that is described withreference to FIGS. 1 to 12. Thus, detailed descriptions thereof will beomitted.

Also, the encapsulation material 30 may be disposed on the substrate 10and have a through-hole to surround the light emitting device 20. Asillustrated in FIG. 25, the through-hole of the encapsulation material30 may have, for example, a circular shape. In addition, thethrough-hole may have various shapes such as a quadrangular shape, anoval shape, a polygonal shape, a trapezoid shape, and a combined shape.

Also, the encapsulation material 30 may be formed of at least onematerial selected from an epoxy molding compound (EMC), an EMCcontaining at least reflection material, white silicon containing areflection material, a photo solder resister (PSR), and a combinationthereof.

Also, the encapsulation material 30 may be molded, dispensed, orscreen-printed on the substrate 10 in a quadrangular plate shape withrounded corners as illustrated in FIG. 25.

More particularly, for example, the encapsulation material 30 may beformed of an epoxy resin composition, a silicon resin composition, amodified epoxy resin composition such as a silicone modified epoxy resincomposition, a modified silicon resin composition such as an epoxymodified silicon resin, a polyimide resin composition, a modifiedpolyimide resin composition, or a resin such as polyphthalamide (PPA), apolycarbonate resin, poly(phenylene sulfide) (PPS), a liquid crystalpolymer (LCP), an ABS resin, a phenol resin, an acrylic resin, and a PBTresin.

Also, titanium oxide, silicon dioxide, titanium dioxide, zirconiumdioxide, potassium titanate, alumina, aluminum nitride, boron nitride,mullite, chrome, or a reflective material such as a white-based ormetal-based component may be contained in the resin.

Also, the encapsulation material 30 may have various shapes. Thus, theshape of the encapsulation material 30 of the light emitting devicepackage 500 in accordance with an embodiment or another embodiment isnot limited to that illustrated in FIG. 23.

For example, the guide member 30-1 may be disposed on each of four sideedges of the encapsulation member 30. As illustrated in FIG. 23, theguide member 30-1 may be a side surface of the encapsulation materialthat is completely inserted into a light incident part 40 a of a lens 40and guides an assembly path of the lens 40. More particularly, asillustrated in FIG. 24, the guide member 30-1 may have a first inclinedsurface 31, a second inclined surface 32, a contact surface 33, and atop surface 34.

Here, as illustrated in FIG. 24, the first inclined surface 31 may be aportion having a relatively gentile inclination to primarily block alight incident part 40 a of the lens 40.

Also, the second inclined surface 32 may be continuously disposed on thefirst inclined surface 31 to secondarily guide the light incident part40 a of the lens 40 and have a second inclination relatively greaterthan that of the first inclination.

Also, the contact surface 33 may be continuously disposed on the secondinclined surface 52 to finally contact and be fixed to the lightincident part 40 a of the lens 40. Thus, the contact surface 33 may havea contact portion. Here, the contact surface 33 may have an inclinedangle of about 90° with respect to an assembly direction toward the lens40.

The top surface 34 may be a flat portion at which the first inclinedsurface 31 starts.

Also, as illustrated in FIG. 24, the first inclined surface 31 may havean inclined internal angle K1 of about 100° to about 135° with respectto the top surface 34, the second inclined surface 32 may have aninclined internal angle K2 of about 150° to about 175° with respect tothe first inclined surface 31, and the contact surface 33 may have aninclined internal angle K3 greater than at least the inclined internalangle K2 with respect to the second inclined surface 32 so that theguide member 30-1 guides the light incident part 40 a of the lens 40 ina primarily gentile inclined direction and then in a secondarilysignificantly inclined direction when the light incident part 40 a ofthe lens 40 is guided.

For example, as illustrated in FIG. 24, a edge R1 between the topsurface 34 and the first inclined surface 31 and a edge R2 between thefirst inclined surface 31 and the second inclined surface 32 may beroundly chamfered to prevent the component from being damaged when thelight incident part 40 a of the lens 40 collides with the components.

Also, as illustrated in FIG. 24, the substrate 10 may contact thecontact surface 33 and also contact a bottom surface 42 of the lightincident part 40 a of the lens 40. Thus, the substrate 10 may determinean assembly position of the light incident part 40 a of the lens 40.Selectively, a top surface 10 a of the substrate 10 may be disposedlower or higher than the bottom surface 42 to seat the lens 40 thereon.

Also, as illustrated in FIG. 25, the encapsulation material 30 may havea substantially quadrangular plate shape with rounded corners. The guidemember 30-1 may be integrally molded with the encapsulation material 30so that the guide member 30-1 is completely inserted into the lightincident part 40 a of the lens 40 at four side edges of theencapsulation material 30.

Also, the guide member 30-1 may be formed of at least one materialselected from an epoxy molding compound (EMC), an EMC containing atleast reflection material, white silicon containing a reflectionmaterial, a photo solder resister (PSR), and a combination thereof.

More particularly, for example, the guide member 30-1 may be formed ofan epoxy resin composition, a silicon resin composition, a modifiedepoxy resin composition such as a silicone modified epoxy resincomposition, a modified silicon resin composition such as an epoxymodified silicon resin, a polyimide resin composition, a modifiedpolyimide resin composition, or a resin such as polyphthalamide (PPA), apolycarbonate resin, poly(phenylene sulfide) (PPS), a liquid crystalpolymer (LCP), an ABS resin, a phenol resin, an acrylic resin, and a PBTresin.

Also, titanium oxide, silicon dioxide, titanium dioxide, zirconiumdioxide, potassium titanate, alumina, aluminum nitride, boron nitride,mullite, chrome, or a reflective material such as a white-based ormetal-based component may be contained in the resin.

The guide member 30-1 may be formed of the same material as theencapsulation material 30 or formed of a material different from theencapsulation material 30. The different material may representmaterials that are not absolutely identical to each other.

As illustrated in FIG. 23, the light emitting device package 500 inaccordance with an embodiment or another embodiment may further includethe lens 40 of which a portion of an inner surface of the light incidentpart 40 a contacts the guide member 30-1 and which is disposed on thesubstrate 10.

FIG. 27 is a plan view illustrating another example of an encapsulationmaterial 30 of FIG. 23.

Referring to FIG. 27, the encapsulation material 30 may have a circularshape on the whole. Also, the encapsulation material 30 may be moldedand completely inserted into the light incident part 40 a of the lens40. In this case, the guide member 30-1 may be an outer circumferentialsurface that circularly surrounds the encapsulation material 30-1.

FIGS. 28 to 30 are cross-sectional views illustrating a process ofaligning the light incident part 40 a of the lens 40 by using the guidemember 30-1 of FIG. 23.

Explaining the process of aligning the lens of the light emitting devicepackage 500 in accordance with an embodiment or another embodiment inmore detail in stages, as illustrated in FIG. 28, the light incidentpart 40 a of the lens 40 may be guided along the first inclined surface31 of the guide member 30-1. Here, the light incident part 40 a of thelens 40 may move along the top surface 34 and then be macroscopicallyguided first by the first inclined surface 31 of the guide member 30-1.

Then, as illustrated in FIG. 29, the light incident part 40 a of thelens 40 may be guided along the second inclined surface 32 of the guidemember 30-1. Here, while the light incident part 40 a is finely guidedby the second inclined surface 32, the light incident part 40 a of thelens 40 may be finely aligned to balance forces of other light incidentparts 40 a that are disposed at a side opposite to the light incidentpart 40 a.

For example, when the light incident part 40 a disposed at one side ofthe lens 40 enters into the second inclined surface 32, the lightincident parts 40 a disposed at the other side of the lens 40 may alsoenter into the second inclined surface 32 to balance the forcestherebetween.

That is, the first inclined surface 31 may align a macroscopic positionof the lens 40, and the second inclined surface 32 may finely align thelens 40 to balance the lens 40.

Then, as illustrated in FIG. 30, the light incident part 40 a of thelens 40 may finally contact the contact surface 33 and be guided alongthe contact surface 33. Then, when the bottom surface of the lightincident part 40 a reaches the substrate 10, and the encapsulationmaterial 30 is completely inserted into the light incident part 40 a ofthe lens 40, the lens 40 may be aligned in a proper position.

Thus, the encapsulation material 30 may be completely inserted into thelight incident part 40 a of the lens 40 to realize slimness of theproduct. Also, the lens 40 may be easily aligned by using the guidemember 30-1 and be improved in assembly accuracy to prevent luminanceand color deviations of a display device, improve light characteristics,and produce high-quality products. In addition, since the lens 40 isaligned in multi-stages by using the first inclined surface 31, thesecond inclined surface 32, the contact surface 33, and the substrate10, the damage of the lens 40 may be prevented, and alignment accuracyof the lens 40 may be improved.

FIG. 31 is a cross-sectional view of a light emitting device package 600in accordance with an embodiment or another embodiment.

Referring to FIG. 31, a light emitting device package 600 in accordancewith an embodiment or another embodiment may further include a hooksurface 57 disposed on the contact surface 33 so that the hook surface57 is engaged with a hook part 43 disposed on a light incident part 40 aof a lens 40.

Thus, the light incident part 40 a of the lens 40 is hooked on the hooksurface 57 to more firmly couple the lens 40 to an encapsulationmaterial 30. Also, it may easily confirm the state in which the lens 40and the encapsulation material 30 are completely aligned with each otherby using the “clack” feel or sound when the lens 40 and theencapsulation material 30 are assembled with each other.

Here, although the hook part 43 and the hook surface 57 are respectivelydisposed on the light incident part 40 a of the lens 40 and the contactsurface 33, the present disclosure is not limited thereto. For example,the hook part 43 and the hook surface 57 may be disposed on the contactsurface 33 and the light incident part 40 a of the lens 40,respectively.

Also, although not shown, a phosphor may be disposed around a lightemitting device 20.

FIG. 32 is a cross-sectional view of a light emitting device package 700in accordance with an embodiment or another embodiment.

As illustrated in FIG. 32, the light emitting device package 700 inaccordance with an embodiment or another embodiment may further includethe encapsulation material 30 and the guide member 30-1, which aredescribed above. Also, the light emitting device package 700 may furtherinclude a substrate 10 on which a light emitting device 20 is seated tosupport the encapsulation material 30 and at least one substrate guidepart 10-1 disposed on a side surface of the substrate 10 to guide anassembly path of a lens 40. A bottom surface 42 of the lens 40 may bedisposed at a same level as a bottom surface of the substrate 10.

Here, the substrate 10 may also have a substantially circular orquadrangular plate shape with rounded corners, like the encapsulationmaterial 30. The substrate guide part 10-1 may be a side surface that iscompletely inserted into a light incident part 40 a of the lens 40 andis engaged with an inner engaging surface 42′ of the lens 40 (as shownin a dotted area A).

Also, the substrate guide part 10-1 may have the same size as the guidemember 30-1. Also, the substrate guide part 10-1 together with theencapsulation material 30 may be completely inserted into the lightincident part 40 a of the lens 40. Although not shown, the hook surface57 of FIG. 31 corresponding to the hook part 43 disposed on the lightincident part 40 a of the lens 40 may also be disposed on the substrateguide part 10-1.

Thus, the encapsulation material 30 and the substrate 10 may becompletely inserted (snap-fitted) into the light incident part 40 a ofthe lens 40 to realize slimmer products.

FIG. 33 is a cross-sectional view of a backlight unit in accordance withan embodiment or another embodiment.

Referring to FIG. 33, a backlight unit in accordance with an embodimentor another embodiment may largely include a substrate 10, a lightemitting device 20, an encapsulation material 30, a guide member 30-1,and a light guide plate 60.

Here, the backlight unit may be disposed on an LCD panel to transmitlight toward the LCD panel. The light emitting device 20, theencapsulation material 30, and the guide member 30-1 may have the sameconstitution and effect as those described with reference to FIGS. 23 to26.

The light guide plate 60 may be disposed in a path of light emitted fromthe light emitting device 20 to transmit the light emitted from thelight emitting device 20 into a wider area. The light guide plate 60 maybe formed of a polycarbonate-based resin, a polysulfone-based resin, apolyacrylate-based resin, a polystyrene-based resin, a polyvinylchloride-based resin, a polyvinyl alcohol-based resin, apolynorbornene-based resin, or a polyester-based resin. In addition, thelight guide plate 60 may be formed of various light transmission resinmaterials. Also, a fine pattern, a fine protrusion, or a diffusion layermay be formed on a surface of the light guide plate 60, or microbubblesmay be formed in the light guide plate 60.

The backlight unit in accordance with an embodiment or anotherembodiment may be a direct-type backlight unit in which the lightemitting device 20 is disposed under the light guide plate 60.

According to the embodiments of the present disclosure as describedabove, the light characteristics may be improved to prevent productdefects from occurring when assembled with the lens, and the lens may bealigned in multi-stages to prevent the lens from being damaged when thelens is aligned. Also, it may prevent the lens having various shapesfrom being misaligned, and the encapsulation material or the substratemay be completely inserted into the light incident part to realize theslimness of the product. Of cause, the range of the present disclosureis not limited to the above-described effects.

Although the light emitting device package and backlight unit having thesame have been described with reference to the specific embodiments,they are not limited thereto. Therefore, it will be readily understoodby those skilled in the art that various modifications and changes canbe made thereto without departing from the spirit and scope of thepresent invention defined by the appended claims.

1-16. (canceled)
 17. A light emitting device package comprising: asubstrate; a light emitting device disposed on the substrate; anencapsulation material disposed on the substrate and configured tosurround the light emitting device; and a guide member disposed on theencapsulation material and having at least one inclined surface to guidea light incident part of a lens, wherein the lens includes at least oneengaging surface to contact the guide member.
 18. The light emittingdevice package of claim 17, wherein: the guide member comprises a topsurface, and the at least one inclined surface of the guide membercomprises: a first inclined surface inclined to the top surface; and asecond inclined surface inclined to the first inclined surface.
 19. Thelight emitting device package of claim 18, wherein the guide memberfurther comprises a round edge disposed between the top surface and thefirst inclined surface.
 20. The light emitting device package of claim17, wherein the guide member comprises: a flat top surface; and a bottomsurface having an area larger than that of the flat top surface tocontact the encapsulation material.
 21. The light emitting devicepackage of claim 17, wherein the guide member comprises: a top surface;a bottom surface configured to contact the encapsulation material; and astopper configured to contact the at least one engaging surface of thelens.
 22. The light emitting device package of claim 21, wherein the atleast one engaging surface of the lens includes a bottom engagingsurface which is supported by the stopper, and the stopper is disposedto be more distant from a light axis of the light emitting device thanthe top surface.
 23. The light emitting device package of claim 17,wherein the at least one engaging surface of the lens includes an innerengaging surface to contact the guide member, and the inner engagingsurface includes an angle of inclination of about 90° with respect tothe substrate.
 24. The light emitting device package of claim 17,wherein the lens further includes a part fixed to the substrate.
 25. Thelight emitting device package of claim 17, wherein the lens is disposedto be more distant from a light axis of the light emitting device thanthe guide member.
 26. A light emitting device package comprising: asubstrate; a light emitting device disposed on the substrate; anencapsulation material disposed on the substrate and configured tosurround the light emitting device; and a guide member including atleast one inclined surface to guide a light incident part of a lens, theat least one inclined surface being formed at a side surface of theencapsulation material, wherein the lens includes a light incident partwhich is an inner hollow portion, the light incident part having anengaging surface to contact the encapsulation material and thesubstrate.
 27. The light emitting device package of claim 26, whereinthe at least one inclined surface comprises: a first inclined surfaceinclined to a top surface of the encapsulation material; and a secondinclined surface inclined to the first inclined surface.
 28. The lightemitting device package of claim 26, wherein the engaging surfaceincludes an inner engaging surface of which an angle of inclination isabout 90° with respect to the substrate.
 29. The light emitting devicepackage of claim 26, wherein the substrate further comprises a sidesurface engaging with the engaging surface.
 30. The light emittingdevice package of claim 26, wherein the lens further includes a bottomsurface disposed at a same level as a bottom surface of the substrate.31. A light emitting device package comprising: a substrate; a lightemitting device disposed on the substrate; a lens including a lightincident part which is an inner hollow portion; and a guide memberincluding at least one inclined surface to guide the light incident partof the lens, the guide member being snap-fitted into the light incidentpart.
 32. The light emitting device package of claim 31, wherein the atleast one inclined surface comprises: a first inclined surface inclineddownwardly toward the substrate; and a second inclined surface inclinedto the first inclined surface.
 33. The light emitting device package ofclaim 31, further comprising: an encapsulation material disposed on thesubstrate and configured to surround the light emitting device, whereinthe guide member is formed on the encapsulation material.